It is extremely common for health care workers to accidentally stick themselves with hypodermic needles during use. Such accidental needle exposures can result in transmission of hepatitis and potentially acquired immune deficiency syndrome--AIDS as well as other communicable diseases. Accidental needle sticks often occur when a blood drawer or any health care professional administering an injection attempts to recap a needle after use or leaves a contaminated exposed needle on work surfaces which may accidentally injure somebody.
The use of hypodermic syringes and needle protectors therefore is widely known. Conventionally, needles are made with hubs and sockets adapted to be attached to the distal end of a syringe. A molded plastic cap is secured to the hub of the needle. This plastic cap is removable to expose the needle for use.
Alternatively, syringes are provided in which the needle is integrally formed as part of the syringe. Again needle guards are provided with the syringe and which are removed prior to use.
A number of attempts have been made in the past to overcome the dangers involved in the use of hypodermic, syringes. The following U.S. Pat. Nos. represent several of these attempts:
______________________________________ 4,643,200 Jennings 253,426 Australia 4,573,975 Frist WO 85/03006 4,610,667 Pedicano 4,654,034 Masters 4,742,910 Staebler 4,743,233 Schneider 4,731,059 Wanderer 4,725,267 Vaillancourt 4,723,943 Spencer 4,664,259 Landis 4,659,330 Nelson 4,643,722 Smith 4,634,428 Cuu 4,631,057 Mitchell 4,425,120 Sampson 4,345,822 Winstead-Hall 3,073,306 Linder ______________________________________
Of particular interest is U.S. Pat. No. 4,742,910, which shows a shield having a sheath attached thereto with an elastic cover which is penetrated by the syringe. While the shield is elastic, the body of the sheath is rigid.
U.S. Pat. No. 4,643,200 discloses a sheath having a longitudinal slot. However, the sheath is rigid and the slot is used for interlocking with a pin on the syringe.
U.S. Pat. No. 4,725,267, Vaillancourt, discloses an elastic shield which is compressible in the longitudinal direction and loosely circumscribes the syringe. The shield extends when released from attachment to the syringe. The shield does not slide along the syringe itself.
U.S. Pat. No. 4,723,943 discloses a sheath having a longitudinal slot. Again, however, the sheath is rigid.
U.S. Pat. No. 4,664,259 discloses a sheath which is bifurcated. The sheath has elastic hinges for holding the sheath away from the needle. However, the sheath does not slide along the barrel of the syringe.
U.S. Pat. No. 4,659,330 discloses a sheath which is attached to a syringe by means of a clip. The clip has an elastic ring which fits about the syringe. The clip is similar in design to clips commonly found on pens. The body of the tubular sheath does not clip or attach onto the syringe body.
U.S. Pat. No. 4,643,722 again shows a sheath having a longitudinal slot. However, the sheath is rigid and the sheath is designed for longitudinal insertion of the needle of the syringe.
Despite the abundance of sheath guards in the prior art, as evidenced by the above listed patents, the low cost easy to use needle sheath remains an elusive goal.